100% Made in Japan Mount adapter.
You have chosen your camera which is a Japanese precision-made instrument,
and you have chosen your lens which is a Japanese precision-made instrument, then
why don't you choose a Japanese precision-made Lens Mount Adapter?
Our camera mount adapters are manufactured in Japan by our meticulous and skilled craftsmen. Our adapters boast remarkable workmanship and are 100% made in Japan so no one can beat our quality.
We recommend individual adapters for every lens purchased/owned.
It is manufactured by the Rayqual, Tokyo, Japan, who are renown specialists
in the manufacture of camera lens mount adapters. The company has enjoyed tremendous success and an enviable reputation in Japan in this specialized area.
Download Instruction Manual PDF Click here
Clean and Maintain your favorite lenses!
Check "Old Lens maintenance tool kit 2 " Click here
100% Made in Japan Mount adapter.
You have chosen your camera which is a Japanese precision-made instrument,
and you have chosen your lens which is a Japanese precision-made instrument, then
why don't you choose a Japanese precision-made Lens Mount Adapter?
Our camera mount adapters are manufactured in Japan by our meticulous and skilled craftsmen. Our adapters boast remarkable workmanship and are 100% made in Japan so no one can beat our quality.
We recommend individual adapters for every lens purchased/owned.
It is manufactured by the Rayqual, Tokyo, Japan, who are renown specialists
in the manufacture of camera lens mount adapters. The company has enjoyed tremendous success and an enviable reputation in Japan in this specialized area.
Download Instruction Manual PDF Click here
Clean and Maintain your favorite lenses!
Check "Old Lens maintenance tool kit 2 " Click here
Attaching Contax/Yashica Mount Lenses to EOS (EF Mount) Bodies
The external appearance varies slightly between two types due to production lot differences, but their performance is identical.
Machined from solid brass as a single-piece construction for high precision and durability.
Mount the lens onto the adapter first. When removing, detach from the camera body first.
Lens exchange while leaving the adapter on the body is not possible.
Be aware that on full-frame sensor EOS cameras or film EOS (EF mount), the lens may interfere with the camera body.
This issue does not occur with EOS cameras using the EF-S mount, such as EOS Kiss Digital, 20D to 60D, and 7D.
About Interference on Full-Frame EOS Cameras
The information below is based on 2015 data and does not include cameras released after that year.
To use Yashica/Contax (Yashikon) mount lenses digitally at their original field of view, a full-frame EOS body is one option.
Other options include full-frame mirrorless cameras from various manufacturers and Leica cameras with live view capability.
Grouping Full-Frame EOS Bodies
A. EOS 1Ds series, EOS 1DX B. EOS 5D, EOS 5D Mark II C. EOS 5D Mark III D. EOS 6D E. EOS 5Ds, EOS 5DsR
The main issue is interference between the aperture lever and side guard at the rear of the lens with the camera’s mirror box, and lenses with a protruding rear element hitting the mirror.
A & B (EOS 1Ds, 1DX, 5D, 5D Mark II)
High probability of interference with the aperture lever and side guard for most Yashikon lenses. Lens modification is recommended.
Mirror interference occurs in both A and B groups, but A (1Ds series) is less prone to interference.
C (EOS 5D Mark III)
Interference is significantly reduced, allowing many lenses to be used without modification.
However, lenses with black▲ guards (same shape as white▲) will still interfere.
The mirror travel path is about 0.2mm lower, slightly increasing the chances of using some lenses that could not be used with B group bodies (15mmF3.5, 18mmF4, 28mmF2.0, 35mmF1.4).
D (EOS 6D)
Aperture lever and guard interference is less than on the 5D Mark III.
Mirror interference is similar to the B group and worse than the 5D Mark III.
E (EOS 5Ds, 5DsR)
Aperture lever and guard interference is similar to C group (5D Mark III).
Mirror interference is similar to B group and worse than the 5D Mark III.
The Tessar 45mm F2.8 requires modification for use on all A to E group bodies.
Summary
The EOS 6D allows the use of the most lenses without modification, but not all.
(Popular lenses like the 35mm F1.4 and 18mm F4 are highly likely to be incompatible.)
If considering lens modification, the EOS 1Ds series and 1DX support the most lenses.
The 5D series falls in between.
※ The information provided here may have exceptions due to variations in individual lenses and is not absolute.
Examples of Mirror Box Interference
CY mount lenses come in three types: white▲, black-slant, and black-corner.
There is also a black▲ version with the same shape as white▲.
※ When using CY-EOS, the green arrow-marked area (aperture lever guard) in the mirror box may interfere and cause scratches. (Excludes EF-S mount cameras.)
The white▲ guard type is the longest and widest, causing larger scratches compared to other mounts.
To prevent scratches inside the mirror box, modification of the guard section is necessary.
(The extent of scratches varies depending on the camera body and lens combination.)
Modification: Trimming approximately 0.3mm from the tip of the guard eliminates interference.
This modification does not affect usage on original Contax bodies.
If modifying the lens yourself, do so at your own risk.
Using a lens that interferes with the mirror box may cause an optical axis misalignment.
This can lead to edge softness in wide-angle lenses and affect infinity focus at larger apertures.
Adapters that claim to prevent interference are thicker, which may prevent achieving infinity focus.
On the EOS 5D Mark II, interference may occur at the upper edge of the mirror box, more so than on the EOS 5D.
This interference occurs when a fan-shaped component at the rear of the lens contacts the mirror box.
(In some lenses, a small triangular protrusion may also cause interference.)
Examples of Mirror Interference
Lenses prone to mirror interference (excluding EF-S mount bodies): 15mm F3.5 18mm F4 28mm F2 45mm F2.8 Macro 60mm F2.8
These lenses have a high probability of being unusable due to interference between the rear element and the mirror.
The following lenses may experience mirror interference due to production variations: 16mm F2.8 Fish-eye 28mm F2.8 35mm F2.8 50mm F1.4
Modification to Prevent Mirror Interference
For the 45mm F2.8 and Macro 60mm F2.8, modifying the rear element retaining ring allows most units to be used.
The 18mm F4 and 28mm F2 may still be unusable even after modification.
Distagon 35mm F1.4
This lens may experience mirror interference depending on individual lens variations.
If interference occurs, the mirror may directly hit the rear element, potentially causing scratches on the lens.
On the EOS 5D, the likelihood of this interference is higher, so extra caution is needed.
